开发一种动力热力学模型,用于Na-bentonite的石灰稳定
Tasneem Ahmadullah1, Maria Chrysochoou2
1Pacific Northwest National Laboratory, Richland, WA, 99354, USA. tasneem.ahmadullah@pnnl.gov.
Geochemical transactions
|July 30, 2025
概括
一个新的动力模型准确地预测了720天内Na-bentonite粘土和冷石灰之间的反应. 该模型捕捉了早期的波特兰石溶解和后期的相变,指导材料的发展.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 纳本托尼特粘土是各种工业应用中的一个关键组成部分.
- 渣通常用作粘合剂和稳定剂.
- 了解这些材料之间的长期反应动力学对于预测性能和耐用性至关重要.
研究的目的:
- 开发和验证第一个动力模型,用于预测Na-bentonite粘土与石反应的固体和孔溶液组成.
- 为了在720天的长时间内模拟反应过程.
- 为了确定矿物质变化的序列和动力学.
主要方法:
- 基于反应速率常数的动力模型的开发.
- 在720天内模拟Na-bentonite和淡化的相互作用.
- 实验验证使用热重力测量分析 (TGA) 和X射线衍射 (XRD) 对固态相进行实验验证.
- 测量pH值和溶解度的水相测量.
主要成果:
- 动力模型成功地预测了大多数使用单一速率常数的实验数据.
- 波特兰石在最初的7天内迅速溶解,随后形成酸盐水合物 (C-S-H),酸水合物 (C-A-H),斯特拉丁石和酸.
- 预测的转变包括托伯莫里特-II形成 (7-28天),蒙莫里隆石溶解和二级阶段降水 (28-90天).
- 实验结果证实波特兰石迅速溶解,并在90天后达到溶液平衡.
结论:
- 开发的动力模型为预测Na-bentonite-lime系统的长期行为提供了有价值的工具.
- 虽然该模型准确地预测了早期反应和溶液化学,但需要进一步的实验技术来验证以后的固相转换.
- 这项研究强调了动力建模在理解工程系统中复杂的地化学反应方面的重要性.
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